area at the optimum time will result in the smallest dose possible received by the unit. If the unit
commander is willing to accept up to a ten percent increase in dose above the minimum possible dose,
personnel may leave the shelters any time between one-half to twice the optimum time.
The unit in the example problem above may depart between H + 1.5 and H + 6
hours without a significant increase in dose to the personnel.
If possible, personnel should improve their shelters while waiting for the optimum exit time. The
estimate of the optimum exit time should be recalculated if significant improvement is made in the
shelters. Improved shelters will mean that the unit should remain in shelters for a longer period of time
to minimize the dose to the personnel.